Did it give the load ratings? Use the single value and multiply it by 4 to see the total weight rating. Now compare this to your trailer's max weight rating. Your tires need to be above this rating.
Run the pressure at the max. Failure to do so will increase the flexing of the tire which will increase the heat generated by the tire. It is the heat that causes bad things to happen.
My suggestion is to get a known brand tire from a dealer you can trust and one who will stand behind (or in front of) the tires they sell.